1999 SL 500 remote key suddenly does not work, yes I replaced the batteries, any idea how to reset the system please?

 

For my 1993 600 MB,with infrared remote lock transmitter,instructions say:
If the vehicle cannot be locked or unlocked it may be necessary to synchronize the lock system.
1. Point window in remote control key at a receiver.
2. Press button momentarily.
3. Lock or unlock vehicle within next 30 seconds with folding key in remote control key in lock cylinder. The remote control should once again be operational.

Transmitter Battery Replacement

Battery replacement
1. Transmitter key
c . Battery compartment lid
f . Batteries
g . Safety catch
Note: Do not spend more than 1 minute replacing batteries, otherwise the signal will have to re-synchronized.[*]Open cover on rear of remote control by pushing safety catch (g) up.[*]Remove batteries and replace with Varta V675 PX or equivalent. Note polarity.[*]Close cover.
[ol][/ol][IMG]local://upfiles/15178/52C5A770C30D4E43B2077777BCCB2554.jpg[/IMG]

 

Thanks for the info, tried your suggestions, no luck, I guess my system is different, or defunct!

 

My process is for the infrared remote system. Your may have newer, radio wave remote system. My OEM owners manual has a section on the remote, battery replacement, and synchronizing. I use www.alladata.com for all repair reference. thanks

 

I just ran across this thread. I had the same issue (had a key that wouldn't lock/unlock the car w/ the infrared fob).

The solution?
1) Point the remote at the receiver (outside the drivers side door)
2) Press a button on the remote briefly (say, the unlock button).
3) Get inside the car, put the key in the ignition, and turn the key to position 2 (just shy of starting the car).

The key remote should now operate normally (mine sure did!).

Hope this helps.